Add 21/90 and 35/81
21/90 + 35/81 is 539/810.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 90 × 9 = 810,
21/90 = 21 × 9/90 × 9 = 189/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
35/81 = 35 × 10/81 × 10 = 350/810 - Add the two like fractions:
189/810 + 350/810 = 189 + 350/810 = 539/810 - So, 21/90 + 35/81 = 539/810
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